While many teenage girls worry about the condition of their skin, sisters Emma and Stacey Picken have told how they lose ALL of their skin every day.
They suffer from a condition called lamellar ichthyosis that speeds up their skin cell turnover, causing the top layer to shed six times faster than a normal, healthy person.
It's estimated that between them they lose four stones of skin every year.
The college students must carefully apply cream to their skin twice a day, meaning it takes them two hours to get ready for college.
Emma, 19, said: "It gets very itchy and can be painful. We have to apply cream head to toe every day.
"We have to vacuum all the time because our skin gets everywhere, and the washing machine always breaks because the cream blocks it up.
"I'm lucky to have a sister who knows exactly what I'm going through. We just get on with it now."
Both of Emma and Stacey's parents are carriers of the ichthyosis gene but had no idea until Emma was born.
The condition causes abnormal scaling and shedding of the skin which usually occurs within the first few days of life.
Sufferers tend to have plate-like scales of skin which often appear brownish in colour. It can also cause overheating as it prevents sweating and it can constrict the blood flow to the fingers and toes as skin tightens.
Sufferers can also experience eye problems, hair loss, and difficulty bending their hand joints. There is currently no cure and the key treatment is regularly applying moisturiser.
Without the cream the sisters' skin becomes very painful and itchy. They lose so much skin that they have to vacuum their house every day and their cream means that their washing machine regularly breaks.
Stacey, 17, from Newton-Aycliffe, County Durham, said: "We put cream on before and after we have a shower in the morning and at night. It takes us about two hours to get ready.
"We can't really apply the cream at college so if it cracks we just have to let it happen.
"It's worst in the summer - because we can't sweat it makes us very dry and itchy. We have to put extra cream on and stay in the shade."
The girls go through a cycle of good and bad patches with their condition. The good phases last up to six weeks, followed by a period of two weeks when they shed extra skin.
Emma said: "We look normal in the good stage - we get our skin up to scratch and then it comes back with a vengeance. We leave a trail of skin behind us in the bad stage."
The girls used to get a lot of stares and comments when at school, but since starting college they say most people are now used to their condition.
Emma said: "Neither me or Stacey have a problem talking about - we would rather people asked than just stared.
"I want to explain it to them. I want to help them understand and then it's fine."
• For more information visit www.ichthyosis.org.uk